AUSTIN, Texas  The man named in a disputed memo as exerting pressure to "sugarcoat" George W. Bush's military record left the Texas Air National Guard a year and a half before the memo supposedly was written, his service record shows.

An order obtained by The Dallas Morning News shows that Col. Walter "Buck" Staudt was honorably discharged March 1, 1972. CBS News reported this week that a memo in which Staudt was described as interfering with officers' negative evaluations of the future president's service was dated Aug. 18, 1973.

That added to mounting questions about the authenticity of documents that seem to suggest Bush sought special treatment as a pilot, failed to carry out a superior's order to undergo a physical exam and was suspended from flying for failing to meet Air National Guard standards.

Staudt, who lives in New Braunfels, Texas, did not return calls seeking comment. His discharge paper was among documents obtained by The Morning News from official sources during 1999 research into Bush's Guard record.

A CBS staffer stood by the story, suggesting Staudt could have continued to exert influence over Guard officials. But a former high-ranking Guard official disputed that, saying retirement would have left Staudt powerless.

Authenticity of the memo and three others included in Wednesday's "60 Minutes" report came in for heavy criticism yesterday, prompting an unusual, on-air defense of the original work. Experts on typography said the memos appeared to have been computer-drafted on equipment not available at the time.

And the widow and son of the officer who supposedly wrote them, Lt. Col. Jerry Killian, who died in 1984, have said it wasn't his nature to keep detailed personal notes.

In its news broadcast yesterday, CBS said the documents were supported by both unnamed witnesses and others, including document examiners.

CBS anchor Dan Rather earlier told The Dallas Morning News that he had heard nothing to make him question the legitimacy of the memos. He attributed the backlash to partisan politics and competitive journalism.

"This story is true. The questions we raised about then-Lieutenant Bush's National Guard service are serious and legitimate," he said. "Until and unless someone shows me definitive proof that they are not, I don't see any reason to carry on a conversation with the professional rumor mill."

The Washington Post quoted Rather as saying CBS had talked to two people who worked with Killian  his superior, retired Maj. Gen. Bobby Hodges, and his administrative assistant Robert Strong  and both described the memos as consistent with what they knew of Killian. Hodges, who told CBS he was "familiar" with the documents, is an avid Bush supporter and "it took a lot for him to speak the truth," the Post quoted Rather as saying.

The Los Angeles Times, however, later quoted Hodges as saying that he believed the memos from Killian were not real. A CBS news executive confirmed that Hodges had changed his story.

Rather's interview with The Morning News concluded before the newspaper determined the date of Staudt's departure, but a CBS staffer with extensive knowledge of the story said later that the departure doesn't derail the story. "From what we've learned, Staudt remained very active after he retired," the staffer said, speaking on condition of anonymity. "He was a very bullying type, and that could have continued."

In the "60 Minutes" report, Rather said of the memo's contents: "Killian says Col. Buck Staudt, the man in charge of the Texas Air National Guard, is putting on pressure to 'sugarcoat' an evaluation of Lt. Bush."

Staudt was the person Bush initially contacted about Guard service, and he was the group commander at Ellington Air Force Base in Houston when Bush arrived there to fly an F-102 jet. He transferred later to Austin, where he served as chief of staff for the Air National Guard.

In the disputed memo, Killian supposedly wrote "(another officer) gave me a message today from group regarding Bush's (evaluation) and Staudt is pushing to sugarcoat it."

It continues: "Austin is not happy either."

The CBS staffer said the memo appears to recognize that Staudt has retired, since it differentiates between his displeasure and that of Austin, where he served his final Guard stint.

But another Texas Air National Guard official who served in that period said the memo appears to wrongly associate Staudt with his group command in Houston, and  based on that mistake  the memo distinguishes his views from that of the Austin Guard.

Retired Col. Earl Lively, director of Air National Guard operations for the state headquarters during 1972 and 1973, said Staudt "wasn't on the scene" after retirement, and that CBS' remote-bullying thesis makes no sense.

"He couldn't bully them. He wasn't in the Guard," Lively said. "He couldn't affect their promotions. Once you're gone from the Guard, you don't have any authority."

Bush has not commented publicly about the CBS report, and aides say his honorable discharge proves he fulfilled his obligations.